Yet observe how, almost to the same extent of obedience he requires the performance of each command, For of God he says, with all thy heart. Of our neighbour, as thyself. Which if it were diligently kept, there would be neither slave nor free man, neither conqueror nor conquered, (or rather, neither prince nor subject,) rich nor poor, nor would the devil be even known, for the chaff would rather stand the touch of fire than the devil the fervour of love; so surpassing all things is the constancy of love.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Hom. 32. in 1 Cor.